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-rw-r--r--debian/transcode/transcode-1.1.7/import/ac3scan.c301
1 files changed, 301 insertions, 0 deletions
diff --git a/debian/transcode/transcode-1.1.7/import/ac3scan.c b/debian/transcode/transcode-1.1.7/import/ac3scan.c
new file mode 100644
index 00000000..d679d4d1
--- /dev/null
+++ b/debian/transcode/transcode-1.1.7/import/ac3scan.c
@@ -0,0 +1,301 @@
+/*
+ * ac3scan.c
+ *
+ * Copyright (C) Thomas Oestreich - June 2001
+ *
+ * This file is part of transcode, a video stream processing tool
+ *
+ * transcode is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * transcode is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Make; see the file COPYING. If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include "libtc/libtc.h"
+
+#include "ac3scan.h"
+#include "magic.h"
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#define MAX_BUF 4096
+static char sbuffer[MAX_BUF];
+
+/*************************************************************************/
+
+/* Utility routines, also used in (and should be cleaned out from):
+ * extract_ac3.c tcscan.c export/aud_aux.c
+ */
+
+static int get_ac3_bitrate(uint8_t *ptr)
+{
+ static const int bitrates[] = {
+ 32, 40, 48, 56,
+ 64, 80, 96, 112,
+ 128, 160, 192, 224,
+ 256, 320, 384, 448,
+ 512, 576, 640
+ };
+ int ratecode = (ptr[2] & 0x3E) >> 1;
+ if (ratecode < sizeof(bitrates)/sizeof(*bitrates))
+ return bitrates[ratecode];
+ return -1;
+}
+
+static int get_ac3_samplerate(uint8_t *ptr)
+{
+ static const int samplerates[] = {48000, 44100, 32000, -1};
+ return samplerates[ptr[2]>>6];
+}
+
+static int get_ac3_nfchans(uint8_t *ptr)
+{
+ static const int nfchans[] = {2, 1, 2, 3, 3, 4, 4, 5};
+ return nfchans[ptr[6]>>5];
+}
+
+static int get_ac3_framesize(uint8_t *ptr)
+{
+ int bitrate = get_ac3_bitrate(ptr);
+ int samplerate = get_ac3_samplerate(ptr);
+ if (bitrate < 0 || samplerate < 0)
+ return -1;
+ return bitrate * 96000 / samplerate + (samplerate==44100 ? ptr[2]&1 : 0);
+}
+
+/*************************************************************************/
+
+int ac3scan(FILE *fd, char *buffer, int size, int *ac_off, int *ac_bytes, int *pseudo_size, int *real_size, int verbose)
+{
+ int bitrate;
+
+ float rbytes;
+
+ int frame_size, pseudo_frame_size;
+
+ if (fread(buffer, 5, 1, fd) !=1)
+ return(TC_IMPORT_ERROR);
+
+ if((frame_size = 2*get_ac3_framesize(buffer+2)) < 1) {
+ tc_log_error(__FILE__, "AC3 framesize=%d invalid", frame_size);
+ return(TC_IMPORT_ERROR);
+ }
+
+ // A single AC3 frame produces exactly 1536 samples
+ // and for 2 channels and 16bit 6kB bytes PCM audio
+
+ rbytes = (float) (size)/1024/6 * frame_size;
+ pseudo_frame_size = (int) (rbytes+0.5); // XXX
+ bitrate = get_ac3_bitrate(buffer+2);
+
+ if(verbose) {
+ tc_log_msg(__FILE__, "AC3 frame %d (%d) bytes | bitrate %d kBits/s | depsize %d | rbytes %f",
+ frame_size, pseudo_frame_size, bitrate, size, rbytes);
+ }
+
+ // return information
+
+ *ac_off=5;
+ *ac_bytes = pseudo_frame_size-(*ac_off);
+ *pseudo_size = pseudo_frame_size;
+ *real_size = frame_size;
+
+ return(0);
+}
+
+static int verbose_flag=TC_QUIET;
+
+int buf_probe_ac3(unsigned char *_buf, int len, ProbeTrackInfo *pcm)
+{
+
+ int j=0, i=0, bitrate, fsize, nfchans;
+
+ char *buffer;
+
+ uint16_t sync_word = 0;
+
+ // need to find syncframe:
+
+ buffer=_buf;
+
+ for(i=0; i<len-4; ++i) {
+
+ sync_word = (sync_word << 8) + (uint8_t) buffer[i];
+
+ if(sync_word == 0x0b77) break;
+ }
+
+ if(verbose_flag & TC_DEBUG)
+ tc_log_msg(__FILE__, "AC3 syncbyte @ %d", i);
+
+ if(sync_word != 0x0b77) return(-1);
+
+ j = get_ac3_samplerate(&buffer[i+1]);
+ bitrate = get_ac3_bitrate(&buffer[i+1]);
+ fsize = 2*get_ac3_framesize(&buffer[i+1]);
+ nfchans = get_ac3_nfchans(&buffer[i+1]);
+
+ if(j<0 || bitrate <0) return(-1);
+
+ pcm->samplerate = j;
+ pcm->chan = (nfchans<2?2:nfchans);
+ pcm->bits = 16;
+ pcm->format = CODEC_AC3;
+ pcm->bitrate = bitrate;
+
+ if(verbose_flag & TC_DEBUG) {
+ tc_log_msg(__FILE__, "samplerate=%d Hz, bitrate=%d kbps, size=%d bytes",
+ pcm->samplerate, bitrate, fsize);
+ }
+
+ return(0);
+}
+
+void probe_ac3(info_t *ipipe)
+{
+
+ // need to find syncframe:
+
+ if(tc_pread(ipipe->fd_in, sbuffer, MAX_BUF) != MAX_BUF) {
+ ipipe->error=1;
+ return;
+ }
+
+ verbose_flag = ipipe->verbose;
+
+ //for single AC3 stream only
+ if(buf_probe_ac3(sbuffer, MAX_BUF, &ipipe->probe_info->track[0])<0) {
+ ipipe->error=1;
+ return;
+ }
+ ipipe->probe_info->magic = TC_MAGIC_AC3;
+ ++ipipe->probe_info->num_tracks;
+
+ return;
+}
+
+#define inc(a) do { if (buf-_buf==len-(a)) return -1; else buf += (a); } while (0)
+int buf_probe_dts (unsigned char *_buf, int len, ProbeTrackInfo *pcm)
+{
+ int i=0;
+ unsigned char *buf = _buf;
+ int frame_type;
+ int sample_count;
+ int has_crc;
+ int nrpcm_samples;
+ int frame_size;
+ int channels;
+ int frequency;
+ int bitrate;
+ int emb_downmix, emb_drc, emb_ts, emb_aux, hdcd_fmt;
+ const int chantab[] = { 1, 2, 2, 2, 2, 3, 3, 4, 4, 5, 6, 6, 6, 7, 8, 8 };
+ const int freqtab[] =
+ { -1, 8000, 16000, 32000, -1, -1, 11025, 22050, 44100, -1, -1, 12000, 24000, 48000, -1, -1 };
+ const int ratetab[] = {
+ 32, 56, 64, 96, 112, 128, 192, 224, 256, 320,
+ 384, 448, 512, 576, 640, 768, 960, 1024, 1152,
+ 1280, 1344, 1408, 1411/*.2*/, 1472, 1536, 1920,
+ 2048, 3072, 3840, -1 /*open*/, 1 /*Variable*/, 0 /*Loss-less*/
+ };
+
+
+ //fprintf(stderr, "DTS DUMP: "); for (i=0; i<16; i++) fprintf(stderr, "%02X", buf[i]); fprintf(stderr, "\n");
+
+ for (i=0; i<len-5; i++, buf++) {
+ if (buf[0]==0x7f && buf[1]==0xfe && buf[2]==0x80 && buf[3]==0x01) {
+ //tc_log_msg(__FILE__, "DTS: found SYNC word at offset 0x%x", i);
+ break;
+ }
+ }
+ /*
+ buf[0] buf[1] buf[2] buf[3] buf[4] buf[5]
+ <---------><-------><------><-------><--------><----------->
+ 1 11111 0 0001111 00001111101101 001001 1101 01111 0 0 0 0 0
+ 1 23456 7 8123456 78123456781234 567812 3456 78123 4 5 6 7 8
+
+ */
+
+ inc(4);
+ frame_type = buf[0]>>7&0x1;
+ sample_count = buf[0]>>2&0x1f;
+ has_crc = buf[0]>>1&0x1;
+ nrpcm_samples = ( (buf[0]&0x1)<<4&0x10 ) | ( buf[1]>>2&0xf );
+ frame_size = ( (buf[1]&0x3)<<16 | buf[2]<<8 | (buf[3]&0xf0 )) >> 4;
+ channels = (buf[3]&0xf)<<2 | (buf[4]>>6&0x3);
+ frequency = (buf[4]&0x3C)>>2;
+ bitrate = (buf[4]&0x3)<<3 | (buf[5]>>5&0x7);
+ emb_downmix = buf[5]>>4&0x1;
+ emb_drc = buf[5]>>3&0x1;
+ emb_ts = buf[5]>>2&0x1;
+ emb_aux = buf[5]>>1&0x1;
+ hdcd_fmt = buf[5]&0x1;
+
+ if (channels>=0 && channels<=0xf) channels=chantab[channels];
+ else channels=2;
+
+ frequency = freqtab[frequency];
+ bitrate = ratetab[bitrate];
+ pcm->samplerate = frequency;
+ pcm->bitrate = bitrate;
+ pcm->chan = channels;
+ pcm->format = CODEC_DTS;
+ pcm->bits = 16;
+
+ if (verbose_flag & TC_DEBUG) {
+ tc_log_info(__FILE__, "DTS: *** Detailed DTS header analysis ***");
+ tc_log_info(__FILE__, "DTS: Frametype: %s", frame_type?"normal frame":"termination frame");
+ tc_log_info(__FILE__, "DTS: Samplecount: %d (%s)", sample_count, (sample_count==31?"not short":"short"));
+ tc_log_info(__FILE__, "DTS: CRC present: %s", has_crc?"yes":"no");
+ tc_log_info(__FILE__, "DTS: PCM Samples Count: %d (%s)", nrpcm_samples, nrpcm_samples<5?"invalid":"valid");
+ tc_log_info(__FILE__, "DTS: Frame Size Bytes: %d (%s)", frame_size, frame_size<94?"invalid":"valid");
+ tc_log_info(__FILE__, "DTS: Channels: %d",channels);
+ tc_log_info(__FILE__, "DTS: Frequency: %d Hz",frequency );
+ tc_log_info(__FILE__, "DTS: Bitrate: %d kbps",bitrate );
+ tc_log_info(__FILE__, "DTS: Embedded Down Mix Enabled: %s", emb_downmix?"yes":"no");
+ tc_log_info(__FILE__, "DTS: Embedded Dynamic Range Flag: %s", emb_drc?"yes":"no");
+ tc_log_info(__FILE__, "DTS: Embedded Time Stamp Flag: %s", emb_ts?"yes":"no");
+ tc_log_info(__FILE__, "DTS: Auxiliary Data Flag: %s", emb_aux?"yes":"no");
+ tc_log_info(__FILE__, "DTS: HDCD format: %s", hdcd_fmt?"yes":"no");
+ }
+
+
+ return 0;
+}
+#undef inc
+
+void probe_dts(info_t *ipipe)
+{
+
+ // need to find syncframe:
+
+ if(tc_pread(ipipe->fd_in, sbuffer, MAX_BUF) != MAX_BUF) {
+ ipipe->error=1;
+ return;
+ }
+
+ verbose_flag = ipipe->verbose;
+
+ //for single DTS stream only
+ if(buf_probe_dts(sbuffer, MAX_BUF, &ipipe->probe_info->track[0])<0) {
+ ipipe->error=1;
+ return;
+ }
+ ipipe->probe_info->magic = TC_MAGIC_DTS;
+ ++ipipe->probe_info->num_tracks;
+
+ return;
+}
+
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